The KPG43 is used for programming the TK690/790/890 series. Assuming they are programmed through the mic connector, the connector is round with 14 compression-type contacts and has a special long shank screw to fix it to the mobile radio's front panel.
You are right, it program's through the mic connector. Many of the lines on the mic connector are on the 25 pin D on the back of the radio. I'm hoping to be able to program it through that.
I bet you could program it through the back. I am pretty sure that all Kenwood does is use a MAX232 equivalent to convert the serial +/- 12v to TTL for the radio. However I don't know if any other pins other than TXD and RXD are required.
Sounds like you may be right, Birken....however, I don't have the service manual so I don't have any way of knowing which pins are TxD, RxD, and ground....can anyone with a service manual for the TK890 help here?
Unfortunately, it is more than just a MAX232. There several transistors on the board, all surface mount. I have no idea how to ID SMDs, so have no way to what the specs of them are. If I could do that, I would have no problem making a schematic like I have posted on the board of the KPG22 / 4, as well as the Maxon SMP-4004C and one of Midland's cables. Can anyone help me with id'ing those transistors?
Brett Kitchens
KF4SQB
kf4sqb "at" wetsnet "dot" com
Of all the things I've lost, it's my mind I miss the most.......
If pin 6 is labeled 'TRD', then that's exactly what it is, 'transmit/receive data'. If I can find it (chances aren't good, I'm a disoraganized slob), I have part of the schematic of a Kenwood remote mount radio that uses such a circuit to convert the standard two-line TXD/RXD circuit from the µprocessor to a single-line TRD circuit for the comms between the head and drawer. If I can find it, I'll send you a schematic of the relevant portion of the circuit. I want to try to use the circuit in question to make a TK-350 a 'remote head' (I know it sounds crazy, but find the thread on the board about the subject, and it will make a little more sense ).
Brett Kitchens
KF4SQB
kf4sqb "at" wetsnet "dot" com
Of all the things I've lost, it's my mind I miss the most.......